If I mash in a beer at 154 then drain off into a kettle. If the wort I drain off into the kettle starts to drop below 154, does conversion still take place in the kettle? Is it creating a more fermentable wort if the temperature of the wort in the kettle drops into the upper 140's?

No I always wait at least 60 minutes in the mash tun for full conversion. My fear is that if I drain the wort into the kettle and it cools off in the kettle that I'm going to end up with a more fermentable wort than intended.

That's a prime reason to do a mashout. If you mash in a kettle, heat it up to 170F for 10 minutes to stop conversion and lock in your body profile. If you mash in a cooler, you can sparge with 170F water to get the same effect.

The mashout stops all enzymatic activity permanently, so no more conversion post-mashout no matter what the temp. Just make sure you have full conversion prior to the mashout. 60 minutes of a solid mash temp with +/- just a few degrees from start to finish does it everytime!

No I always wait at least 60 minutes in the mash tun for full conversion. My fear is that if I drain the wort into the kettle and it cools off in the kettle that I'm going to end up with a more fermentable wort than intended.

Not likely as when you sparge with 168+ water the conversion is halted and since you checked that the conversion was complete in the mash tun your pre-boil specific gravity shouldn't change due to minor temperature flucuations.

I've heard of wort being mashed one day and boiled the next, never tried it myself so I can't speak for the results. Liquid/Dried malt extract is just wort that has been continuously boiled to drive off the water (simplified but you get the idea...) leaving the sugars behind.

Brewing is a process and every decision made during that process affects the end result, so it may very well be that your wort specific gravity goes up a tad while cooling and then again while heating, but I don't believe that it would be a significant amount.

Things like fining/hop additions may be more affected than the specific gravity.

That's a prime reason to do a mashout. If you mash in a kettle, heat it up to 170F for 10 minutes to stop conversion and lock in your body profile. If you mash in a cooler, you can sparge with 170F water to get the same effect.

In theory, that's the case. But if the FG is where it should be, then I wouldn't worry too much.

For me, I do mash out when I fly sparge, but I still have my runnings on to heat while draining the MLT. For when I batch sparge, I don't mash out but I use a hotter infusion to get the grainbed to 168 and then also start the first runnings on to boil right away.

So, I guess the answer is "it depends". If you're not starting the first runnings onto boil as the MLT is draining, and it will be held at a while before that, then a mash out is a good idea.

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